Finding Rare Earth Metals in a Geological Haystack

If you are a typical American, your house is filled with consumer products that rely on rare earth metals to function. Everything from smartphones to LED lighting relies on a group of 17 elements that have similar properties and are often found together in geological deposits. The challenge is finding and accessing those deposits. To use a common analogy, it is like searching for a needle in a haystack.

Researchers are working with the geological haystack in their search for the rare earth metals modern technology demands. One method for finding what they are looking for is to use remote sensing technology based on advanced visible infrared imaging spectrometry. The next generation of this technology, known as AVIRIS-NG, is now being deployed in India.

AVIRIS-NG has already proved up to the challenge. NASA has used it to map surfaces on both the moon and Mars. Australia, Canada, and South Africa have also put the technology to work. The hope is that AVIRIS-NG will improve our ability to find and access the rare earth metal deposits that will allow us to continue pushing technology into the future.

How It All Works

Deploying AVIRIS-NG to find mineral deposits is a complicated and difficult thing. It takes a lot of scientific know-how combined with skill and intuition, according to Rock West Solutions, a California company that deals in both remote signal detection and infrared emission modeling.

In the simplest possible terms, the technology works by scanning a surface for mineral deposits using infrared signals. The subsequent images captured by IR imaging equipment are analyzed for any signatures that might indicate mineral deposits below the surface.

Think about how an ultrasound machine works. Scientists can use ultrasound waves to map geological deposits to some degree. They send sound waves into the ground and then measure them as they come back. The measurements help them determine soil densities, which can be used to create a map. Different densities tell researchers what might be below the surface.

The AVIRIS concept is similar, except that it uses infrared light rather than sound waves. The advantage here is one of detail. The level of detail afforded by AVIRIS makes it a lot more accurate for locating mineral deposits. Moreover, infrared imaging can take place from space. Satellites mounted with AVIRIS-NG equipment can scan vast areas of the earth’s surface in virtually no time at all. You cannot do that with ultrasound imaging.

Why They Are Doing It

So, why is NASA partnering with organizations in India to deploy AVIRIS-NG? There are two reasons. First, the global demand for rare earth metals is greater today than ever before. There are no signs of that demand slowing down, either. We are world built on technology. And for better or worse, our technology depends on those rare earth metals to function.

The second purpose for investing in India is the simple fact that China currently controls upwards of 40% of the world’s known reserves of the rare earth metals in question. They also produce roughly 80% of the metals sold on the world market.

If there is one thing we have learned from the global diamond market over the last 100 years, it is this: allowing any one country too much control over rare commodities allows that country to hold the rest of the world hostage. We need to find other sources of rare earth metals in order to reduce the world’s dependence on China.

Researchers are now engaged in searching for a needle of rare metals in a geological haystack. Let’s hope they find what they are looking for.